Very interesting info in this thread.
I had the same or say similar thing happening to my 2012 QX. But it was fixed for me under warranty. Different outcome than what you 2 had then as solutions to the same problem I had.
http://www.clubarmada.com/forums/showthread.php?t=24056&page=46
My truck was hard to get out of park for 2 days. Then third day, it died on me and would not start even.
My (TCM) transmission control module was the culprit. This piece is inside the transmission pan.
More research from the internet... Just something I copied from the internet.
What is a transmission control module?
QUICK ANSWER
A transmission control module is a mechanism that regulates a vehicle's automatic transmission by processing electrical signals. Sensors electronically send information to the transmission control module, and this information is used to calculate gear shifting. The transmission control module helps the vehicle's transmission work efficiently and dependably.
A transmission control module makes adjustments based on the data it collects from the different signals it receives. Some of the sensors that communicate with the transmission control module are the brake pedal position sensor, the transmission fluid temperature sensor, the turbine speed sensor and the throttle position sensor.
And here is a video of a Infiniti FX35 TCM change. I could not find one for a QX, so this is similar to what they are doing to my car right now at the dealership. Changing out the TCM.
https://www.youtube.com/watch?v=Q5Lc_alSevo